JP2016141381A - Air conditioner for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an air conditioner for a vehicle capable of stably controlling a temperature of conditioned air blown out to a plurality of indoor areas.SOLUTION: Heater means is constituted by a PTC heater 18 having a PTC element. In the case where a preset temperature in one indoor area is different from a preset temperature of a remaining indoor area, opening of an air mix door 54D in a blowout passage 20D on the side where the preset temperature is high is set to be arbitrary opening, and heater capacity of the PTC heater 18 is controlled to become close to the preset temperature in the indoor area on the side where the preset temperature is high. At the same time, opening of an air mix door 54A of a blowout passage 20A on the side where the preset temperature is low is fixed to the opening at which a ratio of blowing air passing through the PTC heater 18 becomes smaller than that in the blowout passage 20A on the side where the preset temperature is high.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a vehicle air conditioner that performs a heating operation using a PTC (Positive Temperature Coefficient) heater.

  In many vehicles equipped with an engine, the vehicle interior is heated using engine coolant. Specifically, in the vehicle air conditioner, engine cooling water is introduced into the heater core, heat exchange is performed between the blown air and the heater core, and the heated air is blown into the vehicle interior.

  Further, as this type of vehicle air conditioner, a vehicle air conditioner has been devised that can independently set and adjust the temperature of the conditioned air that is blown into a plurality of indoor areas (for example, the driver seat area and the passenger seat area). (See Patent Document 1).

JP 58-122213 A

  In recent years, with the widespread use of electric vehicles and the like that are not equipped with engines, the use of PTC heaters as heater means for vehicle air conditioners has been studied. Since the PTC heater incorporates a PTC element having a characteristic that the resistance value increases as the temperature rises, the temperature of the heating element can be maintained below a certain level while suppressing unnecessary power consumption.

  At present, in a vehicle air conditioner that uses a PTC heater as a heater means, as with the vehicle air conditioner described in Patent Document 1, it is hoped that the temperature of conditioned air blown into a plurality of indoor areas can be set and adjusted independently. It is rare. In this case, it may be possible to install PTC heaters individually in the outlet passages for blowing the conditioned air into each indoor area. However, if the PTC heaters are installed individually in each outlet passage, the number of parts increases and the temperature is adjusted. The control for becomes complicated.

  As a countermeasure, a common PTC heater may be used for a plurality of blowing passages. In this case, the heater capacity of the shared PTC heater is set to an arbitrary target temperature, and the vicinity of the PTC heater in each blowing passage. The opening of the air mix door in the corresponding passage is controlled by feeding back the temperature of the section.

  However, when controlling the opening degree of the corresponding air mix door by feeding back the temperature in the vicinity of the PTC heater of each blowing passage in this way, when the set temperatures of one indoor area and the remaining indoor area are different, The operation of the air mix door on the lower set temperature side becomes unstable, and there is a high possibility that the passenger will feel uncomfortable.

  That is, for example, the heater capacity of the PTC heater is arbitrarily set to maximize the opening degree of the air mix door in the blowout passage on the higher set temperature side, while the air mix door in the blowout passage on the lower set temperature side. If the opening degree is relatively narrowed, the amount of air introduced into the PTC heater in the blowing passage on the side where the set temperature is low decreases, and as a result, the feedback temperature in the blowing passage rises. For this reason, the opening degree of the air mix door on the lower set temperature side is further narrowed thereafter, and the operation of the air mix door becomes unstable.

  Therefore, the present invention is intended to provide a vehicle air conditioner that can stably control the temperature of conditioned air blown into a plurality of indoor areas.

  In order to solve the above problems, the vehicle air conditioner according to the present invention is provided corresponding to a plurality of indoor areas (for example, the indoor areas Da and Aa in the embodiment), and individually supplies the conditioned air to each indoor area. A plurality of blow-out passages (for example, the blow-out passages 20D and 20A in the embodiment), a blower (for example, the blower 52 in the embodiment) that takes in air indoors or outdoors and sends the air downstream, and a plurality of the blow-out passages The heater means for raising the temperature of the air that passes through the heater means, and the ratio of the blower air that is provided in each of the blowing passages and that passes through the heater means and the blower air that does not pass through the heater means An air mix door to be adjusted (for example, the air mix doors 54D and 54A of the embodiment), and the temperature of the conditioned air in the indoor area is In the vehicle air conditioner that can be set and adjusted independently, the heater means is composed of a PTC heater having a PTC element, and the set temperature of one indoor area is different from the set temperature of the remaining indoor area. Set the opening of the air mix door in the blowing passage on the higher set temperature side to an arbitrary opening so that the heater capacity of the PTC heater approaches the set temperature of the indoor area on the higher set temperature side In addition to controlling, the opening degree of the air mix door in the blowing passage on the lower set temperature side is fixed to the opening degree in which the ratio of the blown air passing through the PTC heater is smaller than that in the blowing passage on the higher set temperature side. I made it.

  With this configuration, when the set temperature of one indoor area and the set temperature of the remaining indoor area are different, the opening degree of the air mix door is set to an arbitrary opening degree in the blowing passage on the higher set temperature side, The heater capacity of the PTC heater is controlled so as to approach the set temperature of the indoor area on the higher set temperature side. At this time, the opening degree of the air mix door is fixed to an opening degree smaller than the opening degree of the air mix door on the higher set temperature side in the blowing passage on the lower set temperature side. For this reason, in the blowing passage on the side where the set temperature is low, the air with a substantially constant flow rate stably flows in the direction of the PTC heater without being affected by the temperature change of the PTC heater. Therefore, the opening degree of the air mix door does not fluctuate and the passenger in the indoor area does not feel uncomfortable.

Depending on the difference between the set temperature on the higher temperature side and the set temperature on the lower temperature side, the opening degree of the air mix door on the lower temperature setting side of the outlet passage is larger. It is desirable that the ratio of the blown air passing through the PTC heater in the passage is set to be small.
In this case, the temperature of each indoor area can be controlled quickly and accurately.

  According to this invention, when the set temperature of one indoor area is different from the set temperature of the remaining indoor area, the opening degree of the air mix door is set to an arbitrary opening degree in the blowing passage on the higher set temperature side. The heater capacity of the PTC heater is controlled so as to approach the set temperature of the indoor area on the higher set temperature side, and the opening of the air mix door is set to the set temperature in the blowout passage on the lower set temperature side. Since the opening is smaller than the opening of the higher air mix door, it is possible to stably control the temperature of the conditioned air blown to a plurality of indoor areas without being affected by the temperature change of the PTC heater. it can.

It is a block diagram of the vehicle air conditioner which concerns on one Embodiment of this invention. It is a typical horizontal sectional view of an air-conditioning unit concerning one embodiment of this invention. It is a block diagram of the vehicle air conditioner which concerns on one Embodiment of this invention. It is a flowchart which shows an example of control of the vehicle air conditioner which concerns on one Embodiment of this invention. It is a figure for demonstrating the compression ratio-rotation speed area | region which can be utilized with the compressor which concerns on one Embodiment of this invention.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
1-3 is a figure which shows the structure of the vehicle air conditioner 10 which concerns on this embodiment.
The vehicle air conditioner 10 according to this embodiment is mounted on an electric vehicle such as an electric vehicle that does not include an engine (internal combustion engine) as a vehicle drive source. The vehicle air conditioner 10 takes in air from the passenger compartment or outside the passenger compartment, adjusts the temperature of the air and blows it out into the passenger compartment, an air conditioning controller 15 that controls the air conditioner unit 11, and the air conditioning temperature of the passenger. And an air-conditioning setting unit 16 that accepts setting operations and operation mode setting operations.

  Further, the vehicle air conditioner 10 includes a driver-seat-side blowing passage 20D that blows conditioned air into the driver-seat-side indoor area Da and a passenger-seat-side blowing passage 20A that blows conditioned air into the passenger-seat-side indoor area Aa. The air conditioning temperature of the driver seat side indoor area Da and the air conditioning temperature of the passenger seat side indoor area Aa can be set and adjusted independently of each other. The air conditioning setting unit 16 includes a temperature setting unit 16D on the driver's seat side and a temperature setting unit 16A on the passenger seat side.

  In the air conditioning unit 11, a blower 52 for sending air to the downstream side is accommodated in the unit base 51. The unit base 51 is provided with an air intake port 56a for taking in the inside air of the vehicle and an air intake port 56b for taking in the outside air of the vehicle. The air intake ports 56a and 56b are opened and closed by the inside air door 72 and the outside air door 73, respectively. For example, the unit base 51 is adjusted by adjusting the opening degree of the inside air door 72 and the outside air door 73 by the control of the air conditioning control device 15. The flow rate ratio between the inside air and the outside air flowing into the inside is adjusted.

  An air guide duct 17 into which air blown from the blower 52 is introduced is connected to the unit base 51 of the air conditioning unit 11. The air guide duct 17 is provided with an evaporator 53 and an indoor condenser 55 of the heat pump cycle 12 described later, and a PTC (Positive Temperature Coefficient) heater 18 is interposed.

The evaporator 53 performs heat exchange between the low-pressure refrigerant in the heat pump cycle 12 and the vehicle interior atmosphere (air in the air guide duct 17 of the air conditioning unit 11), and passes through the evaporator 53 by heat absorption when the refrigerant evaporates. Cool the air.
The indoor condenser 55 can be radiated by the high-temperature and high-pressure refrigerant in the heat pump cycle 12 and heats the conditioned air passing through the indoor condenser 55.

In the air guide duct 17 of the air conditioning unit 11, an evaporator 53 is interposed on the upstream side close to the unit base 51. As shown in FIG. 2, the inside of the air guide duct 17 downstream of the interposing portion of the evaporator 53 is partitioned into left and right by a partition plate 19, and the driver seat side blowing passage 20D and the passenger seat side blowing passage. It is separated into 20A.
The PTC heater 18 and the indoor condenser 55 are disposed so as to pass through the partition plate 19 and straddle the blowing passage 20D on the driver's seat side and the blowing passage 20A on the passenger seat side. Further, the PTC heater 18 is disposed upstream of the indoor condenser 55 in the blowing passages 20D and 20A.

  Inside the blowing passage 20D on the driver's seat side are a temperature rising flow path 20D-1 where the PTC heater 18 and the indoor condenser 55 are arranged, and a bypass flow path 20D-2 where the PTC heater 18 and the indoor condenser 55 are not arranged. It is separated. On the upstream side of the blowing passage 20D on the driver's seat side, an air mix that adjusts the ratio of the blown air of the blower 52 that passes through the temperature raising flow path 20D-a and the blown air of the blower 52 that passes through the bypass flow path 20D-2. A door 54D is installed. Further, the downstream side of the driver seat side outlet passage 20D is connected to the outlet port 14D facing the indoor area Da on the driver seat side where the heating channel 20D-1 and the bypass channel 20D-2 merge. .

  Similarly, the inside of the blowing passage 20A on the passenger seat side is a temperature rising flow path 20A-1 in which the PTC heater 18 and the indoor condenser 55 are arranged, and a bypass flow path 20A-2 in which the PTC heater 18 and the indoor condenser 55 are not arranged. And are separated. On the upstream side of the blowing passage 20A on the passenger seat side, an air mix that adjusts the ratio of the blown air of the blower 52 that passes through the temperature rising flow path 20A-a and the blown air of the blower 52 that passes through the bypass flow path 20A-2. A door 54A is installed. Further, the downstream side of the blowing passage 20A on the passenger seat side is connected to the blowing port 14A facing the indoor area Aa on the passenger seat side where the heating channel 20A-1 and the bypass channel 20A-2 merge. .

  Temperature sensors 13 </ b> D and 13 </ b> A for detecting the temperature of the air-conditioning air blowing side are installed at the driver's side blowing port 14 </ b> D and the passenger's side blowing port 14 </ b> A, respectively. The temperature signals detected by these temperature sensors 13D and 13A are input to the air conditioning control device 15 and used for various controls by the air conditioning control device 15. The air-conditioning control device 15 controls the operation of the heat pump cycle 12 and the blower 52, which will be described in detail later, and also controls the heater capacity of the PTC heater 18 and the opening degrees of the air mix doors 54D and 54A on the driver side and passenger side. . 1 and 3 is an adjustment circuit for adjusting the heater capacity of the PTC heater 18. Note that the control of the heater capacity is, for example, control of the current that flows through the PTC element.

  The heat pump cycle 12 includes the above-described evaporator 53 and indoor condenser 55, an electric compressor 21 that compresses refrigerant, a heating pressure reducing valve 22, a cooling electromagnetic valve 23, an outdoor heat exchanger 24, and a three-way valve 25. A gas-liquid separator 26 and a cooling pressure reducing valve 27, and these components are connected to each other through a refrigerant flow path 31.

  The compressor 21 is connected between the gas-liquid separator 26 and the indoor condenser 55. For example, the compressor 21 is driven by a motor controlled by the air-conditioning control device 15 and sucks a gas-phase refrigerant (refrigerant gas) from the gas-liquid separator 26 and compresses the refrigerant as a high-temperature and high-pressure refrigerant. It discharges to the indoor capacitor | condenser 55 mentioned above.

On the downstream side of the indoor condenser 55 in the refrigerant flow path 31, the heating pressure reducing valve 22 and the cooling electromagnetic valve 23 are arranged in parallel.
The heating pressure reducing valve 22 is a so-called throttle valve, and after the refrigerant discharged from the indoor condenser 55 is decompressed and expanded, it is a low temperature and low pressure gas-liquid two-phase (liquid phase rich) spray-like refrigerant. To the outdoor heat exchanger 24.

The cooling electromagnetic valve 23 connects the first branch portion 32a and the second branch portion 32b provided on both sides of the heating pressure reducing valve 22 on the refrigerant flow path 31 and bypasses the heating pressure reducing valve 22. For example, it is opened and closed by control by the air conditioning control device 15. The cooling electromagnetic valve 23 is closed during the heating operation, and is opened during the cooling operation.
Thereby, when the heating operation by the heat pump cycle 12 is executed, the refrigerant discharged from the indoor condenser 55 is greatly decompressed by the heating pressure reducing valve 22 and flows into the outdoor heat exchanger 24 in a low temperature and low pressure state. On the other hand, when the cooling operation is performed, the refrigerant discharged from the indoor condenser 55 passes through the cooling electromagnetic valve 23 and flows into the outdoor heat exchanger 24 in a high temperature state.

  The outdoor heat exchanger 24 is disposed outside the passenger compartment, and performs heat exchange between the refrigerant flowing into the interior and the atmosphere outside the passenger compartment. When the heating operation is performed, the outdoor heat exchanger 24 can absorb heat from the outside atmosphere of the vehicle by the low-temperature and low-pressure refrigerant flowing into the interior, and the temperature of the refrigerant is increased by the absorption of heat from the outside atmosphere of the vehicle. When the cooling operation is performed, the outdoor heat exchanger 24 can dissipate heat to the vehicle exterior atmosphere by the high-temperature refrigerant flowing into the interior, and cools the refrigerant by heat radiation to the vehicle exterior atmosphere and ventilation of the condenser fan 24a. .

The three-way valve 25 switches the refrigerant flowing out of the outdoor heat exchanger 24 to the gas-liquid separator 26 or the cooling pressure reducing valve 27 and discharges it. Specifically, the three-way valve 25 is connected to the outdoor heat exchanger 24, the junction 33 disposed on the gas-liquid separator 26 side, and the cooling pressure reducing valve 27, and is controlled by the air conditioning control device 15, for example. Thus, the flow direction of the refrigerant is switched.
When the heating operation is performed, the three-way valve 25 discharges the refrigerant that has flowed out of the outdoor heat exchanger 24 toward the merging portion 33 on the gas-liquid separator 26 side. Further, when the cooling operation is performed, the three-way valve 25 discharges the refrigerant flowing out of the outdoor heat exchanger 24 toward the cooling pressure reducing valve 27.

  The gas-liquid separator 26 is connected between the merging portion 33 in the refrigerant flow path 31 and the compressor 21, separates the gas-liquid refrigerant flowing out from the merging portion 33, and converts the gas-phase refrigerant (refrigerant gas) into the compressor. 21 inhale.

The cooling pressure reducing valve 27 is a so-called throttle valve, and is connected between the three-way valve 25 and the inlet of the evaporator 53. For example, according to the valve opening controlled by the air conditioning control device 15, the three-way valve 25 After the refrigerant flowing out is decompressed and expanded, it is discharged to the evaporator 53 as a gas-liquid two-phase (vapor-phase rich) spray-like refrigerant at a low temperature and low pressure.
The evaporator 53 is connected between the cooling pressure reducing valve 27 and the merging portion 33 (gas-liquid separator 26).

  When performing the heating operation by the heat pump cycle 12, as shown in FIG. 1, the cooling electromagnetic valve 23 is closed, and the three-way valve 25 is connected to the outdoor heat exchanger 24 and the junction 33. The In this case, in the heat pump cycle 12, the high-temperature and high-pressure refrigerant discharged from the compressor 21 heats the conditioned air passing through the blowing passages 20 </ b> D and 20 </ b> A for the driver seat and the passenger seat by the heat radiation in the indoor condenser 55. .

  When performing the cooling operation by the heat pump cycle 12, as shown in FIG. 3, the cooling electromagnetic valve 23 is opened (the heating pressure reducing valve 22 is closed), and the three-way valve 25 is connected to the outdoor heat exchanger 24. The cooling pressure reducing valve 27 is connected. At this time, the air mix doors 54D and 54A of the blowing passages 20D and 20A are closed, for example, on the temperature rising flow paths 20D-1 and 20A-1 side where the indoor condenser 55 exists. In this case, in the heat pump cycle 12, the high-temperature and high-pressure refrigerant discharged from the compressor 21 passes through the indoor condenser 55 and the cooling electromagnetic valve 23 and is radiated to the outdoor atmosphere in the outdoor heat exchanger 24. Thereafter, the refrigerant flows into the cooling pressure reducing valve 27. At this time, the refrigerant is expanded by the cooling pressure reducing valve 27 to form a liquid-rich spray, and then blown out from the blowing passages 20D and 20A on the driver's seat and on the passenger seat side due to heat absorption in the evaporator 53. Cool the conditioned air.

Next, heating control by the PTC heater 18 of the vehicle air conditioner 10 according to this embodiment will be described.
In the heating operation by the PTC heater 18, when the set temperatures of the temperature setting units 16D and 16A on the driver seat side and the passenger seat side are the same, the heater of the PTC heater 18 according to the map stored in advance by the air conditioning control device 15 Ability (for example, energization current) and the opening degree of each air mix door 54D, 54A on the driver's seat side and the passenger seat side are controlled.

When the set temperatures of the temperature setting units 16D and 16A on the driver's seat side and the passenger seat side are different, the air conditioning control device 15 sets the opening degrees of the PTC heater 18 and the air mix doors 54D and 54A as follows. Control.
That is, now, assuming that the setting temperature of the temperature setting unit 16D on the driver's seat side is higher than the setting temperature of the temperature setting unit 16A on the passenger seat side, the air conditioning control device 15 causes the blowing passage on the driver's seat side with a high setting temperature. The opening degree of the air mixing door 54D of 20D is set to an arbitrary opening degree (for example, an opening degree according to the conditions stored in the map in advance), and the heater capacity of the PTC heater 18 is set to the temperature setting unit on the driver seat side. The opening of the air mix door 54A in the blowing passage 20A on the passenger seat side with a low setting temperature is controlled to approach the set temperature of 16D, and the opening of the air mixing door 54D in the blowing passage 20D on the driver seat side is lower. It is fixed at a small set opening (a set opening at which the ratio of conditioned air passing through the PTC heater 18 is small). In addition, when the set temperature of the temperature setting unit 16A on the passenger seat side is higher than the set temperature of the temperature setting unit 16D on the driver seat side, the control of each unit is reversed between the driver seat side and the passenger seat side.

  Here, the opening degree of the air mix door 54A (54D) of the blowing passage 20A (20D) on the lower set temperature side is larger as the difference is larger depending on the difference between the higher temperature side and the lower set temperature. Is set to be small (so that the ratio of the blown air passing through the PTC heater 18 is small). The opening degree of the air mix door 54A (54D) may be set based on a value stored in advance in the map, for example.

An example of heating control by the PTC heater 18 of the vehicle air conditioner 10 will be described with reference to a flowchart shown in FIG.
If it is determined in step S101 that the temperature setting operation has been performed by the air conditioning setting unit 16, it is determined in step S102 whether the set temperature is the same on the driver seat side and the passenger seat side. If they are the same, the process proceeds to step S103, and if they are different, the process proceeds to step S104.
In step S103, the heater capacity of the PTC heater 18 and the opening degrees of the air mix doors 54D and 54A on the driver seat side and the passenger seat side are controlled according to a map stored in advance.
As a result, the indoor area Da on the driver's seat side and the indoor area Aa on the passenger seat side are quickly controlled so as to have the same temperature.

On the other hand, when the process proceeds to step S104, the opening of the air mix door 54D (54A) of the blowing passage 20D (20A) on the higher set temperature side is set to an arbitrary opening (for example, the maximum opening), The heater capacity of the PTC heater 18 is controlled by feeding back a detection signal of the temperature sensor 13D (13A) so as to approach the set temperature on the higher temperature side.
Thereafter, the process proceeds to step S105, where the opening degree of the air mixing door 54A (54D) of the blowing passage 20A (20D) on the lower set temperature side is set to the opening degree of the air mixing door 54D (54A) on the higher setting temperature side. Is also fixed at a small opening.
As a result, in the blowing passage 20 </ b> A (20 </ b> D) on the side where the set temperature is low, the air at a substantially constant flow rate is stabilized in the direction of the PTC heater 18 without being affected by the change in the temperature accompanying the change in the air guide amount of the PTC heater 18. Then flow. Therefore, the temperature of each of the indoor areas Da and Aa on the driver's seat side and the passenger seat side can be controlled to the set temperature without causing unnecessary opening fluctuations of the air mix door 54A (54D).

  As described above, in the vehicle air conditioner 10 according to this embodiment, when the set temperature of the indoor area Da on the driver's seat side and the set temperature of the indoor area Aa on the passenger seat side are different, the blowing on the higher set temperature side The opening degree of the air mix door 54D (54A) is set to an arbitrary opening degree in the passage 20D (20A), and the heater capacity of the PTC heater 18 becomes the set temperature of the indoor area Da (Aa) on the higher set temperature side. The opening of the air mix door 54A (54D) is controlled so as to approach the opening 20A (20D) on the lower set temperature side, and the opening of the air mix door 54D (54A) on the higher set temperature side. Is fixed at a smaller opening. For this reason, in the vehicle air conditioner 10 according to this embodiment, even if the set temperature of the indoor area Da on the driver's seat side and the set temperature of the indoor area Aa on the front passenger seat are different, the amount of air introduced Without being influenced by the temperature change of the PTC heater 18, the temperature of the conditioned air blown out to the driver seat side indoor area Da and the passenger seat side indoor area Aa can be controlled stably.

  Further, in the vehicle air conditioner 10 according to this embodiment, when the set temperature in the driver seat side indoor area Da and the set temperature in the passenger seat side indoor area Aa are different, the blowout passage 20A on the lower set temperature side is provided. The opening degree of the air mixing door 54A (54D) of (20D) is set so that the opening degree decreases as the difference between the set temperature on the higher temperature side and the set temperature on the lower temperature side increases. For this reason, in this vehicle air conditioner 10, the temperature of the conditioned air blown out to the indoor area Da on the driver's seat side and the indoor area Aa on the passenger seat side can be quickly and accurately adjusted to a desired temperature.

  By the way, in the vehicle air conditioner 10 according to this embodiment, lubricating oil is mixed in the refrigerant circulating in the heat pump cycle 12, and the lubricating oil causes the rotating portion (bearing), the friction portion (compressing portion), and the like of the compressor 21 to be used. The lubrication is performed. However, since the refrigerant is introduced to the suction side of the compressor 21 at a low pressure, the durability of the compressor 21 may be severe depending on the operating conditions. For this reason, in the vehicle air conditioner 10 according to this embodiment, measures to be described later are taken according to the rotation speed of the compressor 21 and the compression ratio (discharge pressure / suction pressure).

  FIG. 5 is a diagram in which a boundary line L, which becomes severe in terms of durability, is experimentally examined in the relationship between the rotation speed of the compressor 21 and the compression ratio. In the figure, the region below the boundary line L is a region (OK region) in which each part can be lubricated without failure by the lubricating oil in the refrigerant, and the region above the boundary line L is the region in the refrigerant. This is a region where the lubricating oil is insufficient (NG1 region and NG2 region). The NG1 region and the NG2 region are bordered by a predetermined rotational speed N of the compressor 21.

(Countermeasures in the NG1 area)
In the NG1 region, the operation speed of the compressor 21 is low, and the flow rate of the refrigerant circulating in the heat pump cycle 12 is small, so the operation of the compressor 21 is stopped.

(Countermeasures in the NG2 area)
In the NG2 region, since the operating speed of the compressor 21 is too high and the compression ratio of the refrigerant is large, the operating speed of the compressor 21 is reduced so as to shift to the OK region as indicated by an arrow A in FIG. At this time, the compression ratio of the compressor 21 also decreases as the operating speed of the compressor 21 decreases.
As another countermeasure, as shown by an arrow B in FIG. 5, the compression ratio in the compressor 21 is increased by increasing the opening of the heating pressure reducing valve or the cooling pressure reducing valve so as to shift to the OK region. Decrease.
These measures are appropriately selected according to the driving situation.

In addition, this invention is not limited to said embodiment, A various design change is possible in the range which does not deviate from the summary. For example, in the above-described embodiment, the vehicle air conditioner is configured to blow conditioned air to the driver seat side indoor area and the passenger seat side indoor area. It may be blown out. Further, the number of indoor areas for blowing out the conditioned air is not limited to two, and may be three or more.
Furthermore, the vehicle to which the vehicle air conditioner is applied is not limited to an electric vehicle, and may be another vehicle such as a fuel cell vehicle.

DESCRIPTION OF SYMBOLS 10 ... Vehicle air conditioner 18 ... PCT heater 19 ... Partition plate 20D, 20A ... Outlet passage 52 ... Blower 54D, 54A ... Air mix door Da, Aa ... Indoor area

Claims (2)

A plurality of outlet passages provided corresponding to a plurality of indoor areas, and individually blowing out conditioned air to each indoor area;
A blower that takes in air indoors or outdoors and sends air downstream;
Heater means for raising the temperature of air passing through the plurality of blowing passages;
An air mix door that is provided in each of the blowing passages and adjusts the ratio of the blower air of the blower that passes through the heater means and the blower air of the blower that does not pass through the heater means,
In the vehicle air conditioner in which the temperature of the conditioned air in the indoor area can be independently set and adjusted,
The heater means is constituted by a PTC heater having a PTC element,
If the set temperature of one indoor area is different from the set temperature of the remaining indoor areas,
The opening degree of the air mix door of the blowing passage on the higher set temperature side is set to an arbitrary opening degree, and the heater capacity of the PTC heater is controlled to approach the set temperature of the indoor area on the higher set temperature side. With
The opening degree of the air mix door of the blowing passage on the lower set temperature side is fixed to an opening degree in which the ratio of the blown air passing through the PTC heater is smaller than that of the blowing passage on the higher set temperature side. Vehicle air conditioner.   Depending on the difference between the set temperature on the higher temperature side and the set temperature on the lower temperature side, the opening degree of the air mix door on the lower temperature setting side of the outlet passage is larger. The vehicle air conditioner according to claim 1, wherein a ratio of the blown air passing through the PTC heater in the passage is set to be small.

Images